1: 92 percent / PhSK / dimethylformamide / 3 h / 86 °C 2: acid 3: 92 percent / EtN(i-Pr)2, (Bu)4NI / CH2Cl2 / 32 h / Heating 4: 1.) LDA, 2.) mCPBA / 1.) THF, -78 deg C, 2.) hexane, 25 deg C, 5 h 5: 95 percent / CH2Cl2 / 15 h / -45 °C 6: 63 percent / Burgess' reagent 7: 100 percent / pyridine 8: 65 percent / OsO4 9: DBU / toluene / 2 h / 105 °C 10: 75 percent / pyridine, DMAP / 24 h / 25 °C 11: 100 percent / HF*pyridine / acetonitrile / 11 h / 0 °C 12: tetrahydrofuran / 0.17 h / -78 °C 13: tetrapropylammonium perruthenate, NMO, molecular sieves / CH2Cl2 / 0.25 h / 25 °C 14: 1.) t-BuOK, 2.) benzeneseleninic anhydride, 3.) t-BuOK 15: pyridine, DMAP / 20 h / 25 °C 16: 94 percent / TASF / tetrahydrofuran / 1 h / 25 °C 17: 1.) LHMDS / 1.) THF, 2.) THF, 0 deg C, 1 h 18: HF, pyridine / acetonitrile / 1 h / 0 °C 19: H2 / Pd/C / ethanol / 1 h View Scheme

1: 63 percent / Burgess' reagent 2: 100 percent / pyridine 3: 65 percent / OsO4 4: DBU / toluene / 2 h / 105 °C 5: 75 percent / pyridine, DMAP / 24 h / 25 °C 6: 100 percent / HF*pyridine / acetonitrile / 11 h / 0 °C 7: tetrahydrofuran / 0.17 h / -78 °C 8: tetrapropylammonium perruthenate, NMO, molecular sieves / CH2Cl2 / 0.25 h / 25 °C 9: 1.) t-BuOK, 2.) benzeneseleninic anhydride, 3.) t-BuOK 10: pyridine, DMAP / 20 h / 25 °C 11: 94 percent / TASF / tetrahydrofuran / 1 h / 25 °C 12: 1.) LHMDS / 1.) THF, 2.) THF, 0 deg C, 1 h 13: HF, pyridine / acetonitrile / 1 h / 0 °C 14: H2 / Pd/C / ethanol / 1 h View Scheme

1: 95 percent / CH2Cl2 / 15 h / -45 °C 2: 63 percent / Burgess' reagent 3: 100 percent / pyridine 4: 65 percent / OsO4 5: DBU / toluene / 2 h / 105 °C 6: 75 percent / pyridine, DMAP / 24 h / 25 °C 7: 100 percent / HF*pyridine / acetonitrile / 11 h / 0 °C 8: tetrahydrofuran / 0.17 h / -78 °C 9: tetrapropylammonium perruthenate, NMO, molecular sieves / CH2Cl2 / 0.25 h / 25 °C 10: 1.) t-BuOK, 2.) benzeneseleninic anhydride, 3.) t-BuOK 11: pyridine, DMAP / 20 h / 25 °C 12: 94 percent / TASF / tetrahydrofuran / 1 h / 25 °C 13: 1.) LHMDS / 1.) THF, 2.) THF, 0 deg C, 1 h 14: HF, pyridine / acetonitrile / 1 h / 0 °C 15: H2 / Pd/C / ethanol / 1 h View Scheme

acetic anhydride; sodium hydrogencarbonate; thiourea in pyridine; ethanol; chloroform; acetone

hydrogen; palladium on activated charcoal in ethanol 1 h; Yield given;

water; trifluoroacetic acid T=20°C; Hydrolysis; 0.25 h;

1.1: 2,6-lutidine / CH2Cl2 / 12 h / -45 °C 2.1: 6.6 mg / aq. hydrogen peroxide; aq. Na2CO3 / ethyl acetate / 1 h / 20 °C 3.1: 92 percent / Dess-Martin periodinane / CH2Cl2 / 1 h / 20 °C 4.1: 97 percent / pyridinium p-toluenesulfonate / CH2Cl2 / 0.08 h / 20 °C 5.1: KHMDS / tetrahydrofuran / 0.5 h / -78 °C 5.2: 89 percent / tetrahydrofuran / 1 h / -78 °C 6.1: 91 percent / tetrakis(triphenylphosphine)palladium / diethyl ether; tetrahydrofuran / 1 h / 20 °C 7.1: 88 percent / N-chlorosuccinimide / methanol / 10 h / 20 °C 8.1: 89 percent / pyridinium p-toluenesulfonate; 2-methoxypropene / CH2Cl2 / 0.05 h / 20 °C 9.1: 80 percent / lithium diisopropyl amide; MoO5*pyridine*HMPA / tetrahydrofuran / 0.92 h / -23 °C 10.1: 92 percent / DMAP / CH2Cl2 / 0.5 h / 20 °C 11.1: 68 percent / DBN / toluene / 10 h / Heating 12.1: 86 percent / OsO4; pyridine / diethyl ether; tetrahydrofuran / 18 h / 20 °C 13.1: 86 percent / DBU / toluene / 4 h / Heating 14.1: pyridinium p-toluenesulfonic acid / methanol / 0.5 h / 20 °C 15.1: 15 mg / DMAP; imidazole / dimethylformamide / 5 h / 20 °C 16.1: 97 percent / H2 / Pd(OH)2 / ethanol / 1 h / 20 °C 17.1: 94 percent / pyridine / CH2Cl2 / 1 h / -78 - 0 °C 18.1: 66 percent / DMAP / CH2Cl2 / 6 h / 20 °C 19.1: 83 percent / tetrahydrofuran / 0.33 h / -78 °C 20.1: 88 percent / HF*pyridine / tetrahydrofuran / 2 h / 20 °C 21.1: 94 percent / pyridine / CH2Cl2 / 3 h / 20 °C 22.1: 80 percent / TASF / tetrahydrofuran / 48 h / 20 °C 23.1: 77 percent / LHMDS / tetrahydrofuran / -78 - 0 °C 24.1: 84 percent / Zn; aq. AcOH / 16 h / 20 °C View Scheme

1.1: 6.6 mg / aq. hydrogen peroxide; aq. Na2CO3 / ethyl acetate / 1 h / 20 °C 2.1: 92 percent / Dess-Martin periodinane / CH2Cl2 / 1 h / 20 °C 3.1: 97 percent / pyridinium p-toluenesulfonate / CH2Cl2 / 0.08 h / 20 °C 4.1: KHMDS / tetrahydrofuran / 0.5 h / -78 °C 4.2: 89 percent / tetrahydrofuran / 1 h / -78 °C 5.1: 91 percent / tetrakis(triphenylphosphine)palladium / diethyl ether; tetrahydrofuran / 1 h / 20 °C 6.1: 88 percent / N-chlorosuccinimide / methanol / 10 h / 20 °C 7.1: 89 percent / pyridinium p-toluenesulfonate; 2-methoxypropene / CH2Cl2 / 0.05 h / 20 °C 8.1: 80 percent / lithium diisopropyl amide; MoO5*pyridine*HMPA / tetrahydrofuran / 0.92 h / -23 °C 9.1: 92 percent / DMAP / CH2Cl2 / 0.5 h / 20 °C 10.1: 68 percent / DBN / toluene / 10 h / Heating 11.1: 86 percent / OsO4; pyridine / diethyl ether; tetrahydrofuran / 18 h / 20 °C 12.1: 86 percent / DBU / toluene / 4 h / Heating 13.1: pyridinium p-toluenesulfonic acid / methanol / 0.5 h / 20 °C 14.1: 15 mg / DMAP; imidazole / dimethylformamide / 5 h / 20 °C 15.1: 97 percent / H2 / Pd(OH)2 / ethanol / 1 h / 20 °C 16.1: 94 percent / pyridine / CH2Cl2 / 1 h / -78 - 0 °C 17.1: 66 percent / DMAP / CH2Cl2 / 6 h / 20 °C 18.1: 83 percent / tetrahydrofuran / 0.33 h / -78 °C 19.1: 88 percent / HF*pyridine / tetrahydrofuran / 2 h / 20 °C 20.1: 94 percent / pyridine / CH2Cl2 / 3 h / 20 °C 21.1: 80 percent / TASF / tetrahydrofuran / 48 h / 20 °C 22.1: 77 percent / LHMDS / tetrahydrofuran / -78 - 0 °C 23.1: 84 percent / Zn; aq. AcOH / 16 h / 20 °C View Scheme

1: 1.) t-BuMgCl / 1.) THF, -78 deg C, 2.) THF, -78 deg C 2: 1.) (MeBO)3, pyridine, 2.) TiCl2(OiPr)2, 3.) pinacol, DMAP 3: BuLi / tetrahydrofuran / -78 - 0 °C 4: DIBAL / CH2Cl2 / -78 °C 5: 2,6-lutidine / CH2Cl2 / -23 °C 6: O2, TPP / CH2Cl2 / Irradiation 7: Bu3SnH, AIBN / benzene / Heating 8: H2 / Pd/C / ethanol 9: CSA / CH2Cl2 / -23 °C 10: 66 percent / Et2Zn / toluene / 0 °C 11: 77 percent / Dess-Martin reagent / CH2Cl2 12: 84 percent / H2 / Pd(OH)2 / ethanol 13: pyridine / CH2Cl2 / -45 °C 14: TBAF, AcOH / tetrahydrofuran 15: 86 percent / PPTS / benzene / Heating 16: 100 percent / K2CO3 / methanol; tetrahydrofuran 17: 100 percent / SmI2, HMPA / tetrahydrofuran; methanol 18: TBAF, BHT / tetrahydrofuran 19: NaOMe, BHT / methanol 20: 1.) PhB(OH)2, 2.) 2,6-lutidine, 3.) H2O2, NaHCO3 21: 92 percent / Dess-Martin reagent / CH2Cl2 22: 89 percent / PPTS / CH2Cl2 23: 89 percent / KHMDS / -78 °C 24: 91 percent / Pd(PPh3)4 / diethyl ether 25: 1.) NCS, 2.) 2-methoxypropene, PPTS / 1.) MeOH, 2.) CH2Cl2 26: 1.) LDA, 2.) MoO5*pyr*HMPA / 1.) THF, -23 deg C, 2.) THF, -23 deg C 27: 92 percent / DMAP / CH2Cl2 28: 68 percent / DBN / toluene / Heating 29: 86 percent / OsO4, pyridine / diethyl ether 30: 86 percent / DBU / toluene / Heating 31: PPTS, MeOH 32: imidazole / dimethylformamide 33: 97 percent / H2 / Pd(OH)2 / ethanol 34: 94 percent / pyridine / CH2Cl2 / -78 - 0 °C 35: 66 percent / DMAP / CH2Cl2 36: 83 percent / tetrahydrofuran / -78 °C 37: 88 percent / HF*pyridine / tetrahydrofuran 38: 94 percent / pyridine / CH2Cl2 39: 80 percent / TASF / tetrahydrofuran 40: 77 percent / LHMDS / tetrahydrofuran / -78 - 0 °C 41: 84 percent / Zn, aq. AcOH View Scheme

1: BuLi / tetrahydrofuran / -78 - 0 °C 2: DIBAL / CH2Cl2 / -78 °C 3: 2,6-lutidine / CH2Cl2 / -23 °C 4: O2, TPP / CH2Cl2 / Irradiation 5: Bu3SnH, AIBN / benzene / Heating 6: H2 / Pd/C / ethanol 7: CSA / CH2Cl2 / -23 °C 8: 66 percent / Et2Zn / toluene / 0 °C 9: 77 percent / Dess-Martin reagent / CH2Cl2 10: 84 percent / H2 / Pd(OH)2 / ethanol 11: pyridine / CH2Cl2 / -45 °C 12: TBAF, AcOH / tetrahydrofuran 13: 86 percent / PPTS / benzene / Heating 14: 100 percent / K2CO3 / methanol; tetrahydrofuran 15: 100 percent / SmI2, HMPA / tetrahydrofuran; methanol 16: TBAF, BHT / tetrahydrofuran 17: NaOMe, BHT / methanol 18: 1.) PhB(OH)2, 2.) 2,6-lutidine, 3.) H2O2, NaHCO3 19: 92 percent / Dess-Martin reagent / CH2Cl2 20: 89 percent / PPTS / CH2Cl2 21: 89 percent / KHMDS / -78 °C 22: 91 percent / Pd(PPh3)4 / diethyl ether 23: 1.) NCS, 2.) 2-methoxypropene, PPTS / 1.) MeOH, 2.) CH2Cl2 24: 1.) LDA, 2.) MoO5*pyr*HMPA / 1.) THF, -23 deg C, 2.) THF, -23 deg C 25: 92 percent / DMAP / CH2Cl2 26: 68 percent / DBN / toluene / Heating 27: 86 percent / OsO4, pyridine / diethyl ether 28: 86 percent / DBU / toluene / Heating 29: PPTS, MeOH 30: imidazole / dimethylformamide 31: 97 percent / H2 / Pd(OH)2 / ethanol 32: 94 percent / pyridine / CH2Cl2 / -78 - 0 °C 33: 66 percent / DMAP / CH2Cl2 34: 83 percent / tetrahydrofuran / -78 °C 35: 88 percent / HF*pyridine / tetrahydrofuran 36: 94 percent / pyridine / CH2Cl2 37: 80 percent / TASF / tetrahydrofuran 38: 77 percent / LHMDS / tetrahydrofuran / -78 - 0 °C 39: 84 percent / Zn, aq. AcOH View Scheme